The edible portions of gizzards from chicken and other poultry carcasses are harvested in several steps. These steps in processing the gizzard include removing the viscera from the gizzard, after which the gizzard is split and opened for washing and removal of the pocket lining from the split gizard.
Gizzard peeling machines usually employ a pair of peeling rolls mounted in side-by-side relation with each other. These peeling rolls have helical teeth along their lengths, with the teeth of the rolls being mutually spaced apart sufficiently to define an elongate space for receiving a gizzard placed on the rotating rolls. This space is too small to permit passage therethrough of the gizzard itself. The counter-rotating action of the toothed peeling rolls removes the pocket lining and draws that lining downwardly through the space until the peeled gizzard rests on the rolls. The gizzard thus becomes properly aligned along a longitudinal axis parallel to the rolls, and the helical teeth on the rotating rolls draws the gizzard longitudinally along that path. The gizzard then is removed from the peeler rolls for further processing.
Because the proper operation of such gizzard peeling apparatus requires a firm engagement of the gizzard with the toothed peeling rolls, some peeler machines use tampers which urge the gizzards inwardly toward the nip of the peeling rolls. These tampers preferably move back and forth relative to the longitudinal gizzard-receiving space defined by the nip between the rolls, the tampers thus alternately moving away from the rolls to accommodate incoming gizzards and moving toward the rolls to tamp those gizzards firmly against the helical teeth on the rotating rolls.
The preferred way of driving the tampers in prior-art peeler apparatus is to mechanically link the tamper to at least one of the rotating peeling rolls at the so-called free or undriven end of that roll. This seemed like a relatively inexpensive and effective way of utilizing the motion of the driven peeling rolls to operate the tamper. However, disadvantages to this driving arrangement have become evident. A principal disadvantage of the tamper drive arrangement in the prior art is that the mechanical load imparted to the peeling rolls damages the bushings of the rolls. This damage may arise from the nonuniform or periodic nature of the radial load imparted to the rotating rolls by driving the oscillating tamper into and out of tamping engagement with a gizzard on the rolls. The problem of damage to the support bushings of the peeling rolls has worsened as the preferred length of these rolls has increased for better performance. The rolls themselves are driven from the end opposite to the location of the tamper, so that a common drive mechanism coupled both to the tamper and the corresponding end of the drive rolls heretofore was considered not feasible without major redesign and reconstruction of the gizzard peeler apparatus.